The present paper deals with the use of different fibers (steel–SF, glass–GF and polypropylene-PF) to reinforce concretes and shotcretes (manufactured with a sodium silicate based set-accelerating admixture) for tunnel linings in order to compare rheological and mechanical behaviour of set accelerated fiber reinforced mixtures with respect to plain concrete. The effect of fibres on rheological and mechanical properties was evaluated. Shotcrete rebound was closely related to the dosage of set-accelerating admixture other than type and dosage of fibers. Strength gain and mechanical properties were strongly influenced by both the casting method and the dosage of set-accelerating product. Spraying and set accelerator dosage determine a sharp decrease in compressive strength compared that of concrete placed and vibrated without sodium silicate. Furthermore, the test results indicated that punching shear strength of FR mixtures was lower than that of steel mesh reinforced shotcrete without fibers as a consequence of the poor quality of the cement matrix due to the set-accelerator addition. Use of set accelerating admixture reduced the fiber-matrix bond lowering the punching shear strength of FR mixtures.

(2015). Evaluation of rheological and mechanical properties of fiber reinforced set-accelerated shotcretes for tunnel lining [conference presentation - intervento a convegno]. Retrieved from http://hdl.handle.net/10446/57344

Evaluation of rheological and mechanical properties of fiber reinforced set-accelerated shotcretes for tunnel lining

COPPOLA, Luigi;BUOSO, Alessandra;LORENZI, Sergio
2015-01-01

Abstract

The present paper deals with the use of different fibers (steel–SF, glass–GF and polypropylene-PF) to reinforce concretes and shotcretes (manufactured with a sodium silicate based set-accelerating admixture) for tunnel linings in order to compare rheological and mechanical behaviour of set accelerated fiber reinforced mixtures with respect to plain concrete. The effect of fibres on rheological and mechanical properties was evaluated. Shotcrete rebound was closely related to the dosage of set-accelerating admixture other than type and dosage of fibers. Strength gain and mechanical properties were strongly influenced by both the casting method and the dosage of set-accelerating product. Spraying and set accelerator dosage determine a sharp decrease in compressive strength compared that of concrete placed and vibrated without sodium silicate. Furthermore, the test results indicated that punching shear strength of FR mixtures was lower than that of steel mesh reinforced shotcrete without fibers as a consequence of the poor quality of the cement matrix due to the set-accelerator addition. Use of set accelerating admixture reduced the fiber-matrix bond lowering the punching shear strength of FR mixtures.
2015
Coppola, Luigi; Buoso, Alessandra; D'Alessandro, Franco; Lorenzi, Sergio
File allegato/i alla scheda:
File Dimensione del file Formato  
SP-040_final_rev.pdf

Solo gestori di archivio

Versione: publisher's version - versione editoriale
Licenza: Licenza default Aisberg
Dimensione del file 718.44 kB
Formato Adobe PDF
718.44 kB Adobe PDF   Visualizza/Apri
Pubblicazioni consigliate

Aisberg ©2008 Servizi bibliotecari, Università degli studi di Bergamo | Terms of use/Condizioni di utilizzo

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10446/57344
Citazioni
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact